The Sun on Sunday and the Sunday Mirror are both understood to have suffered sales drops at the weekend following their respective 10p cover price rises, according to early circulation estimates from well-placed sources.

Both Sunday tabloids are said to have had sales declines of more than 3%, following the price rises and editorial revamps backed by advertising campaigns.

The Sun on Sunday's circulation dropped 3.6% on the previous weekend to 1.85m copies, on 22 September, the first day of its 10p cover price rise to 70p, according to unofficial industry estimates.

According to the latest official Audit Bureau of Circulations figures, the Sun on Sunday reported an average weekly headline circulation of 1.92m copies in August, which was down 0.56% on the previous month and down 10.17% on the year.

In the same month, the Sunday Mirror reported a headline circulation of 1.06m, up 1.72% on July and down 3.4% on the year.

Sunday tabloid sales are understood to have been down generally last weekend, with the Daily Star Sunday dropping about 4%, the Mail on Sunday down 3% and the Sunday Express dipping 2.4%.

Official ABC figures for September will be published on 11 October.

News UK and Trinity Mirror declined to comment.

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